‘Let me say right off I’m a witch,” the title character declares at the start of “Sowa’s Red Gravy,” and thank goodness she does, because it’s the only clear moment of Diane Richards’ play.

This messy stew, inspired by Harlem Renaissance writers and Southern folklore, stars the lovely Lonette McKee as the 110-year-old Sowa. From an apartment littered with skulls, playing cards and magic potions, she regales us with accounts of her past lives as a white Hollywood movie star, an African warrior and a Louisiana voodoo priestess.

She also introduces us to her fellow practitioners of the black arts: the witch Windy Willow (Toni Seawright) and the demonic Belozah (Kene Holliday).

Looking like Cab Calloway in his sharply tailored, brightly colored suits, Belozah lusts after Willow. Unfortunately for him she’s a lesbian who, as she colorfully puts it, “loves me some tangy tang.” Sowa is equally besotted with Sapphire (Jonathan Peck), but he’s under the spell of Luwanna (Kimberly “Q”), another sorceress who admits, “Those three husbands I had, I had to kill ’em.”

Although a recording of “I Put a Spell on You” is played over and over again, this New Federal Theatre production stops far short of spellbinding. With its endless, vernacular-filled monologues and musical sequences featuring a lithe dancer (Iris Wilson) and African drummer (David D. Wright), it feels like a series of short stories randomly pulled together into a nearly incoherent package.

Among the more egregious episodes are one in which an anxious white man (Aaron Fried) comes to Sowa for help —“Soon we white people will be outnumbered,” he sputters — and another in which a Jewish baker (Fried again) tells how he used magic to escape the horrors of the Holocaust. That last is followed by the ensemble exuberantly singing and dancing “Hava Nagila.”

Although Richards clearly loves the stories and folklore that inspired her, the sheer indulgence of what she’s wrought is stultifying. Nor does it help that director Woodie King Jr. encouraged the performers to ham it up.

Only McKee emerges with her dignity intact. It’s a shame that the woman who made such a a heartbreaking Billie Holiday in “Lady Day at Emerson’s Bar & Grill” more than a quarter century ago can’t find better material today than this indigestible “Gravy.”